Bed bugs (Cimex lectularius and Cimex hemipterus) are small insects that feed off the blood of humans and other warm-blooded hosts. Bed bugs usually spend daylight hours in dark enclosed sites and have a preference for crevices in fabric, wood and paper. The bed bugs create a micro-environment in which they live during the day. In recent years, there has been a world-wide increase in the prevalence of bed bugs.
Bed bugs are attracted to the heat and carbon dioxide given off by warm-blooded hosts, which make bedrooms, and especially mattresses and headboards, an ideal environment for them to take refuge. Bed bugs are known for being elusive, transient and mainly active at night, making their detection difficult. They may be transferred between locations on furniture, bags, clothes or people.
As personal injury litigation injury is on the rise, hotels, transport providers and many other service sectors are at risk of expensive court actions should a customer receive a bite from, or pick up, bed bugs. Therefore, there is a need, at least in hotel rooms, to easily identify whether a location is inhabited by bed bugs so that it can be treated.
The most common method of detection of bed bugs is by identifying the bites, which they inflict on the bed occupant. The bites inflict a dermatological reaction in humans, but this usually cannot be felt until some minutes or hours and in some cases days after the bug bites and the first indication of a bite usually comes from the desire to scratch the bite site. Generally, it shows up as either a raised red bump or a flat welt, often in groups of three or so following the line of a vein.
Clearly waiting for the bed bugs to bite has many disadvantages, for example the bites are very similar to mosquito bites and therefore difficult to identify. Detecting the bugs before they bit would be better. One method of detecting bed bugs is to have a readily available light source, such as a torch, and shining it on the bed during the night to try and catch any bed bugs that are active. A disadvantage of this is that movement of the person in the bed may alert the bed bugs and they can then scatter.
Another current method of detecting bed bugs is to use glue traps, often in conjunction with a heat pad and carbon dioxide source to attract the bugs. Such devices are expensive and require the use of an electrical source to keep the carbon dioxide source and heat pad running. This makes them unsuitable for use in hotel rooms due to the expense of the initial purchase and subsequent cost of running.
Using double-sided carpet tape as, effectively, another form of glue trap has been proposed. However, the bed bugs may find ways to avoid the tape and the tape is unsightly.
The worldwide increase in the prevalence of bed bugs, referred to earlier, is caused by reasons which need not be explored here. But it highlights the need for a solution to the problems they cause and this brief review of known attempts to detect and eliminate them (all of which are based around active capture) shows that there is no clear starting point—and indeed no satisfactory universal solution from which the problem may be tackled.